Peptide receptors on astrocytes.
In recent years, it has become apparent that astrocytes (at least in vitro) harbor functional receptors to almost all possible neurotransmitters (with the potential noticeable exception of acetylcholine nicotinic receptors). Peptides are no exception, since receptors to all neuropeptides known to be produced in the CNS have been found on cultured astrocytes, and the presence of many of these has been confirmed on astrocytes in vivo. A variety of methodologies have been used to detect peptide receptors on astrocytes, as summarized in the current review. Special emphasis is also put on the possible roles that peptides may play in the regulation of astrocyte functions. These include proliferation, morphology, release of eicosanoids and arachidonic acid, induction of calcium transients and calcium waves, and control of internal pH, glucose uptake, glycogen metabolism, and gap junctional conductance. Recent data concerning the effects of natriuretic peptides on astrocytes are reviewed, and why these peptides may constitute priviledged tools to test the effects of peptides on astrocyte-neuron interactions is also discussed.
Deschepper
C F
CF
Neurobiology and Vasoactive Peptide Laboratory, Institut de recherches cliniques de Montréal, Quebec, Canada.
D000818:Animals; D001253:Astrocytes / Q000502:physiology*; D006801:Humans; D009479:Neuropeptides / Q000502:physiology*; D018000:Receptors, Peptide / Q000502:physiology*
D009479:Neuropeptides; D018000:Receptors, Peptide